1. Field of the Invention
The present invention relates to numerical controllers, and particularly, to a numerical controller capable of changing machining conditions in accordance with machining information.
2. Description of the Related Art
An end position and a speed of a tool are instructed in a machining program, and the machining is executed based on a tool path. A general machining program does not describe additional information related to an aim or a situation of a movement of the tool and a feature of the tool path such as a setting at the program producing including blocks by a CAM in an instruction of each block.
As to the conventional technology for instructing the details of a tool movement in the instruction of each block in the machining program, for example, Japanese Patent No. 3647043 discloses a technology of performing acceleration/deceleration control using an instruction program including, within one block, a plurality of acceleration/deceleration start positions, time constants of the acceleration/deceleration control to be started in the acceleration/deceleration start positions, and target speeds by the acceleration/deceleration.
According to the technique disclosed in Japanese Patent Application Laid-Open No. 2009-076018, the machining is made possible in the acceleration/deceleration setting suitable for a desired location, for example, by performing deceleration in a location required of accuracy by adding an instruction for changing an acceleration/deceleration time constant.
In a machining program illustrated as an example in FIG. 5, coordinate values are uniformly instructed in Blocks N1 to N10, but each block is characterized by a movement aim and a movement situation of the tool 3. For example, a path in a dotted line is an air cut section, Block N1 is an approach section in which the tool approaches a workpiece, and Blocks N7 to N9 are pick feed sections. There occurs a problem with a detailed adjustment to the settings of numerical control such as a machining speed in accordance with the feature of the tool path such as the movement aim and the movement situation of the tool, but according to the general machining program, where to change the setting of the numerical control cannot be determined by the program alone. In addition, it is impossible to make an adjustment of the setting of the numerical control in a lump for locations having the same feature of the tool path.
As to this problem, in the technology according to Japanese Patent No. 3647043 and Japanese Patent Application Laid-Open No. 2009-076018, the movement of the tool in each block can be in detail instructed on some level, but that instruction is limited to direct and specific matters, and does not include information related to abstract features of the tool path such as the movement aim and situation of the tool. Therefore even if these conventional technologies are introduced, it cannot be determined where to change the setting in the machining program in accordance with the feature of the tool path such as the movement aim and movement situation of the tool, and the locations having the same feature of the tool path cannot be collectively adjusted.